TAT-DEF-Elk-1 (TDE) is a cell-penetrable peptide inhibitor of Elk-1 that achieves inhibition by mimicking and specifically interfering with the DEF domain of Elk-1. TAT-DEF-Elk-1 blocks Elk-1 phosphorylation and prevents Elk-1 nuclear translocation without interfering with ERK or MSK1 activation. TAT-DEF-Elk-1 is a useful tool for analyzing the role of Elk-1 in the development of neuronal plasticity.

Physicochemical Properties

Molecular Formula	C155H259N57O40
Molecular Weight	3561.07
Exact Mass	3560.001
CAS #	1220751-16-5
Related CAS #	TAT-DEF-Elk-1 TFA
PubChem CID	168013667
Appearance	White to off-white solid powder
LogP	-18
Hydrogen Bond Donor Count	58
Hydrogen Bond Acceptor Count	51
Rotatable Bond Count	124
Heavy Atom Count	252
Complexity	8360
Defined Atom Stereocenter Count	30
SMILES	CC[C@H](C)[C@@H](C(=O)O)NC(=O)[C@H](CC1=CN=CN1)NC(=O)[C@H](C(C)C)NC(=O)[C@H](CCC(=O)N)NC(=O)[C@H](C)NC(=O)[C@H](CO)NC(=O)CNC(=O)[C@H](CO)NC(=O)[C@H](CO)NC(=O)[C@@H]2CCCN2C(=O)[C@H](CC3=CC=CC=C3)NC(=O)[C@H](CCC(=O)N)NC(=O)[C@H](CC4=CC=CC=C4)NC(=O)[C@H](CO)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCCCN)NC(=O)[C@H](C)NC(=O)[C@@H]5CCCN5C(=O)[C@H](CO)NC(=O)[C@@H]6CCCN6C(=O)[C@@H]7CCCN7C(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCC(=O)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCCNC(=N)N)NC(=O)CN
InChi Key	NXUDNUMTWDPXTO-CNIZJYQSSA-N
InChi Code	InChI=1S/C155H259N57O40/c1-9-83(6)120(149(251)252)208-137(239)103(71-88-73-175-80-183-88)201-144(246)119(82(4)5)207-134(236)99(51-54-116(162)220)189-121(223)84(7)184-138(240)106(76-214)187-118(222)74-182-123(225)105(75-213)203-140(242)108(78-216)205-142(244)111-46-29-64-209(111)146(248)104(70-87-34-14-11-15-35-87)202-133(235)98(50-53-115(161)219)197-136(238)102(69-86-32-12-10-13-33-86)200-139(241)107(77-215)204-135(237)101(68-81(2)3)199-131(233)90(36-16-19-55-156)188-122(224)85(8)185-141(243)110-45-28-65-210(110)147(249)109(79-217)206-143(245)112-47-30-66-211(112)148(250)113-48-31-67-212(113)145(247)100(44-27-63-181-155(173)174)198-130(232)96(43-26-62-180-154(171)172)194-128(230)94(41-24-60-178-152(167)168)195-132(234)97(49-52-114(160)218)196-129(231)95(42-25-61-179-153(169)170)193-127(229)93(40-23-59-177-151(165)166)192-126(228)92(38-18-21-57-158)191-125(227)91(37-17-20-56-157)190-124(226)89(186-117(221)72-159)39-22-58-176-150(163)164/h10-15,32-35,73,80-85,89-113,119-120,213-217H,9,16-31,36-72,74-79,156-159H2,1-8H3,(H2,160,218)(H2,161,219)(H2,162,220)(H,175,183)(H,182,225)(H,184,240)(H,185,243)(H,186,221)(H,187,222)(H,188,224)(H,189,223)(H,190,226)(H,191,227)(H,192,228)(H,193,229)(H,194,230)(H,195,234)(H,196,231)(H,197,238)(H,198,232)(H,199,233)(H,200,241)(H,201,246)(H,202,235)(H,203,242)(H,204,237)(H,205,244)(H,206,245)(H,207,236)(H,208,239)(H,251,252)(H4,163,164,176)(H4,165,166,177)(H4,167,168,178)(H4,169,170,179)(H4,171,172,180)(H4,173,174,181)/t83-,84-,85-,89-,90-,91-,92-,93-,94-,95-,96-,97-,98-,99-,100-,101-,102-,103-,104-,105-,106-,107-,108-,109-,110-,111-,112-,113-,119-,120-/m0/s1
Chemical Name	(2S,3S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-5-amino-2-[[(2S)-2-[[(2S)-2-[[2-[[(2S)-2-[[(2S)-2-[[(2S)-1-[(2S)-2-[[(2S)-5-amino-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-6-amino-2-[[(2S)-2-[[(2S)-1-[(2S)-2-[[(2S)-1-[(2S)-1-[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-5-amino-2-[[(2S)-2-[[(2S)-2-[[(2S)-6-amino-2-[[(2S)-6-amino-2-[[(2S)-2-[(2-aminoacetyl)amino]-5-carbamimidamidopentanoyl]amino]hexanoyl]amino]hexanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-oxopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]amino]-5-carbamimidamidopentanoyl]pyrrolidine-2-carbonyl]pyrrolidine-2-carbonyl]amino]-3-hydroxypropanoyl]pyrrolidine-2-carbonyl]amino]propanoyl]amino]hexanoyl]amino]-4-methylpentanoyl]amino]-3-hydroxypropanoyl]amino]-3-phenylpropanoyl]amino]-5-oxopentanoyl]amino]-3-phenylpropanoyl]pyrrolidine-2-carbonyl]amino]-3-hydroxypropanoyl]amino]-3-hydroxypropanoyl]amino]acetyl]amino]-3-hydroxypropanoyl]amino]propanoyl]amino]-5-oxopentanoyl]amino]-3-methylbutanoyl]amino]-3-(1H-imidazol-5-yl)propanoyl]amino]-3-methylpentanoic acid
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light.
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

ln Vitro	Elk-1 phosphorylation on Ser383/389 serves two purposes: it causes SRE-dependent gene expression and Elk-1 nuclear translocation [1]. TAT-DEF-Elk-1 (5-10 μM; 1 hour) does not interfere with CREB, MSK-1, or ERK phosphorylation, but it specifically inhibits glutamate-induced elk-1 activation [1]. Treatment with TAT-DEF-Elk-1 (5 μM; 2 hours) significantly inhibited the expression of c-Fos, Zif268 and JunB, but had no effect on c-Jun [1].
ln Vivo	TAT-DEF-Elk-1 (ip; 1 mg/kg; daily; 14 days) showed antidepressant activity in mice, which reduced immobility similar to the reference antidepressants fluoxetine and desipramine (DMI)[2].
Cell Assay	Western Blot Analysis[1] Cell Types: Neuronal Tested Concentrations: 5 μM; 10 μM Incubation Duration: 1 hour Experimental Results: diminished Elk-1 expression, no effect on ERK, MSK-1 or CREB phosphorylation. RT-PCR[1] Cell Types: Primary striatal neurons Tested Concentrations: 5 μM Incubation Duration: 2 hrs (hours) Experimental Results: c-Fos, Zif268 and JunB mRNA levels were diminished, but c-Jun was not affected.
Animal Protocol	Animal/Disease Models: C57Bl6 mice (3-6 months old males) suffered social defeat stress [2] Doses: 1mg/kg; Route of Administration: intraperitoneal (ip) injection; daily; 14 days Experimental Results: Social defeat was reversed by repeated TDE administration Resulting in a decrease in Bdnf expression in the hippocampus.
References	[1]. Lavaur J, et al. A TAT-DEF-Elk-1 peptide regulates the cytonuclear trafficking of Elk-1 and controls cytoskeleton dynamics.J Neurosci. 2007 Dec 26;27(52):14448-58.

Solubility Data

Solubility (In Vitro)

H2O : ~5 mg/mL (~1.40 mM)

Solubility (In Vivo)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	0.2808 mL	1.4041 mL	2.8081 mL
	5 mM	0.0562 mL	0.2808 mL	0.5616 mL
	10 mM	0.0281 mL	0.1404 mL	0.2808 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.